Our investigations of the catalytic mechanism of action of rabbit skeletal muscle pyruvate kinase will be continued using reagents which block the essential sulfhydryl and lysyl epsilon-amino groups. The various components of the enzyme systems in P. oleovorans, C. tropicalis, and liver microsomes which hydroxylate fatty acids, alkanes, and a variety of drugs and other foregin compounds will be characterized. Attempts will be made to further purify cytochrome P-450 and to establish the role of phospholipid in the system, the basis for the very broad specificity, and the mechanism of action, including the possible role of superoxide or other free radical species.